EVN User Experiment Pipeline Feedback


Pipeline feedback for experiment EG040B. If you have any comments on this experiment please email the address below.
A detailed description of the pipeline output is available.

Last updated: Fri Oct 30 16:46:23 CET 2009 muehle@jive.nl

General Comments. ( Brief data summary and scan listing )
L band (18 cm) EVN experiment, observed on 08 June 2009. The data rate was 1024 Mbps (8 x 16 MHz subbands, dual polarization, two-bit sampling). The target sources 'NGC3227' and 'NGC4639' were calibrated using the phase-reference sources 'J1016+2037' and '3C274'. '3C345' was also observed as fringe finder. In this pipeline reduction, Ef served as reference antenna and as plot reference, i.e. the plots show baselines to Ef.
9 EVN stations were scheduled in this experiment: Ar, Ef, Jb, On, Mc, Nt, Tr, Ur, and Wb. At Ar, the Mark5A recorder lost connection to the field system and no data were recorded between 22:13 and 23:03 UT. Mc lost scans 15-19 due to a Mark5 software block after a disk change. At Jb, the MkII telescope was used for this experiment, skipping every fourth scan of a cycle. Ur observed as a one-bit station until 19:31 UT, when the sources dropped below the horizon. Wb observed with 12 telescopes in phased-array mode.

The EVN reliability indicator (ERI) for this experiment was ERI = 0.93 . ERI* = 0.93 . (Ef=1, Jb=1, Mc=0.91, Nt=1, On=1, Tr=1, Ur=1, Wb=1, Ar=0.79)

Plots of the autocorrelations
Comments.
low-level RFI at almost all stations; Wb: amplitude of IF2 (= subband 1) most of the time way off; Mc: amplitude of IF1 (= subband 0) most of the time way off; 216 pages

plots of the uncalibrated amplitude and phase against time
Comments.
phases of the fringe-finders (and phase-reference sources) can be followed even in the uncalibrated data; Ur: sources below the horizon after 19:31 UT; Ar: joined at 20:30 UT, no data recorded between 22:13 and 23:03 UT; 32 pages

Plots of the uncalibrated amplitude and phase against frequency channel
Comments.
phases can be followed in fringe finders and phase-reference sources; Mc: low amplitude in IF1 (= subband 0), as usual; 214 pages

The uncalibrated amplitude and phase of the crosshand correlations against frequency channel
Comments.
phases can be followed in 3C345 and the phase-reference sources; 108 pages

TSYS against time
Comments.
Wb: T_sys noisy in IF2+3; On: spikes of high T_sys or a number of outliers in all IFs except for IF5+6 between ~21:00 and 22:30 UT; Mc: T_sys in IF1/R and IF2/R at times ~10^3K, T_sys up to ~1500K in IFs 7+8 between 20:00 and 20:50 UT; 15 pages

Telescope sensitivities from the a priori TSYS and Gain curves (the square of this number gives the antenna noise (SEFD) in Jy - the smaller the better).
Comments.
curves match closely those of T_sys vs. time; 15 pages

Fringe-fit phase solutions (including Parallactic Angle correction).
Comments.
reference antenna: Ef, drift in phases reflects the parallactic angle correction; Ar: Mark 5A recorder lost connection to the field system between 22:13 and 23:03 UT, fast fringe rotation afterwards; 15 pages

Fringe-fit delay solutions
Comments.
reference antenna: Ef; delays of the order of nanoseconds, at most a few tens of nanoseconds (e.g. for Mc/IF1, Tr/IF1R+2R); 15 pages

Fringe-fit rate solutions
Comments.
reference antenna: Ef; rates of the order of a few mHz; 15 pages

Telescope bandpasses
Comments.
reference antenna: Ef; in general, bandpasses look good, phases flat and close to zero; Mc: phases of IF2/R+L deviate significantly from zero; 2 pages

Calibrated amplitude and phase against time (a priori amplitude calibration and fringe-fit solutions applied).
Comments.
looking fine; Mc: IF1/R+L noisier than the other channels (bandpass limitations); 32 pages

Calibrated amplitude and phase against frequency channel
Comments.
Mc: drop-off in amplitude in IF1+2+8, noisy phases in IF1; 214 pages

Naturally weighted dirty map (not useful for bright sources) produced before self-cal of:
NGC4639: pdf , or FITS .
NGC3227: pdf , or FITS .
3C274: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
J1016+2037: pdf (not available) , or FITS (not available) .
Comments.

Uniformly weighted dirty map (not useful for bright sources) produced before self-cal of:
NGC4639: pdf , or FITS .
NGC3227: pdf , or FITS .
3C274: pdf (not available) , or FITS (not available) .
3C345: pdf (not available) , or FITS (not available) .
J1016+2037: pdf (not available) , or FITS (not available) .
Comments.

Phase corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
NGC4639 (not available) .
NGC3227 (not available) .
3C274 .
3C345 .
J1016+2037 .
Comments.
refant: Ef; phase corrections within a couple of degrees for 3C345 and 3C274, a bit larger for the weaker J1016+2037; Mc: no solutions for 3C345 (missed that scan); 12-15 pages per source

Amplitude corrections applied to a priori calibrated and fringe-fitted data by self-calibration.
NGC4639: pdf (not available) , or text file (not available) , or statistical summary (not available) .
NGC3227: pdf (not available) , or text file (not available) , or statistical summary (not available) .
3C274: pdf , or text file , or statistical summary .
3C345: pdf , or text file , or statistical summary .
J1016+2037: pdf , or text file , or statistical summary .
Comments.
Mc: gain corrections in IF1/R+L very large, no solutions for 3C345 (missed that scan); 12-15 pages per source

Telescope sensitivities (the total AMP gain applied during both a priori and self calibration; the square of this number gives the antenna noise (SEFD) in Jy).
Comments.
Mc: sensitivity in IF1 significantly decreased; 15 pages

Residual closure phase (visibility closure phase with model closure phase subtracted) for:
NGC4639 (not available) .
NGC3227 (not available) .
3C274 .
3C345 .
J1016+2037 .
Comments.
closure phases larger for loops that include Mc (noisy phases in IF1); 7-16 pages per source

Calibrated visibilities and the source model of:
NGC4639 (not available) .
NGC3227 (not available) .
3C274 .
3C345 .
J1016+2037 .
Comments.
generally very good agreement between data and models; Mc: noisy amplitudes and phases in IF1 (see above); Wb: amplitudes in IF2+3 wiggely (noisy T_sys); 32 pages per source

Calibrated visibilities against u,v distance for:
NGC4639: pdf , or png .
NGC3227: pdf , or png .
3C274: pdf , or png .
3C345: pdf , or png .
J1016+2037: pdf , or png .
Comments.

u,v coverage for:
NGC4639: pdf , or png .
NGC3227: pdf , or png .
3C274: pdf , or png .
3C345: pdf , or png .
J1016+2037: pdf , or png .
Comments.

Crude maps of sources:
NGC4639: pdf , or FITS .
NGC3227: pdf , or FITS .
3C274: pdf , or FITS .
3C345: pdf , or FITS .
J1016+2037: pdf , or FITS .
Comments.